2012-12-18 Richard Biener <rguenther@suse.de>

	PR tree-optimization/55555
	* tree-ssa-loop-niter.c (idx_infer_loop_bounds): Properly
	analyze evolution of the index for the loop it is used in.
	* tree-scalar-evolution.c (instantiate_scev_name): Take
	inner loop we will be creating a chrec for.  Generalize
	fix for PR40281 and prune invalid SCEVs.
	(instantiate_scev_poly): Likewise - pass down inner loop
	we will be creating a chrec for.
	(instantiate_scev_binary): Take and pass through inner loop.
	(instantiate_array_ref): Likewise.
	(instantiate_scev_convert): Likewise.
	(instantiate_scev_not): Likewise.
	(instantiate_scev_3): Likewise.
	(instantiate_scev_2): Likewise.
	(instantiate_scev_1): Likewise.
	(instantiate_scev_r): Likewise.
	(resolve_mixers): Adjust.
	(instantiate_scev): Likewise.

	* gcc.dg/torture/pr55555.c: New testcase.
	* gcc.dg/vect/vect-iv-11.c: Adjust.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@194578 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 6 insertions, 1 deletions

diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
index a9b70778952..4a09999f434 100644
--- a/gcc/tree-ssa-loop-niter.c
+++ b/gcc/tree-ssa-loop-niter.c
@@ -2671,7 +2671,12 @@ idx_infer_loop_bounds (tree base, tree *idx, void *dta)
       upper = false;
     }
 
-  ev = instantiate_parameters (loop, analyze_scalar_evolution (loop, *idx));
+  struct loop *dloop = loop_containing_stmt (data->stmt);
+  if (!dloop)
+    return true;
+
+  ev = analyze_scalar_evolution (dloop, *idx);
+  ev = instantiate_parameters (loop, ev);
   init = initial_condition (ev);
   step = evolution_part_in_loop_num (ev, loop->num);